Treatment of hydrocarbons



p w. F. RITTMAN AND 0. B. IDUTTON.

Patented Jan. 11,1921.

INVENTORS WITNESSES UNITED STATES PATENT OFFICE.

WALTER F. BITTIl/IAN AND CLARENCE B. DUTTON, OF PITTSBURGH, PENNSYLVANIA.

TREATMENT or HYDROCARBONS.

Application filed February 5, 1917. Serial No. 146,728.

To all whom it may concern:

Be it known that we, lVAL'rER F. RITTMAN and CLARENCE B. DUTTON, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, citizens of the United States, have invented or discovered certain new and useful Improvements in the Treatment of Hydrocarbons, of'which improvement the following is a specification.

In treating hydrocarbons by the taper- -phase cracking process (described at length in Department of the Interior Bulletin #:114) which comprises subjecting vaporized oils to the action of heat and pressure in a retort, the products of reaction differ widely, ranging from high-boiling point products condensable at a temperature only slightly less than the temperature at the discharge end of the retort to fined gases. Some of these products as propane, butane, butylene, pentane, etc., having a Baum gravity varying from 70 upward, are extremely "olatile and cannot be condensed by means within the range of commercial practibility, and will escape from-a condenser mingled with the fixed gases. Ithas been found, however, that if this mixture of gases and the highly volatile vapors, hereinafter termed wild gasolene,-be passed through relatively heavy oil, such as naphtha, which is formed in the vaporphase cracking process above referred to at the same time as the wild gasolene, the latter will be separated from the fixed gases and will mix with the naphtha. By thus blending anoil having a heavy Baum gravity such as 53 Baum, and so low as to render it unfit as a motor fuel, with the wild gasolene, a liquid is produced having a higher gravity such as 58 or 60 Baum and entirely suitable forlu'se in internal combustion engines.

The term naphtha, as used in the claim, includes relatively high boiling heavy gravity oils, having a Baum gravity so low as to render them unfit for motor fuel as such, but of sufiiciently high Baum gravity to make the mixture thereof with wild gasolene available for use as motor fuel. The order of the Baum gravity of the oils includedunder the term naphtha, is indicated, as above stated, to be about 53 Baum.

The heavier constituents of the blend or bons in the liquid state, but when the mix- Specification of Letters Patent.

Patented Jan. 11,1921.

ture is atomized in a carbureter, the volatile hydrocarbons or wild gasolene becomes the carrying agent and will help tremendously to carry the heavier constituents through the carbureter and manifolds into the cylinders of the motor for combustion. Through the use of this wild gasolene, not only its own volume is made available as motor fuel, but an even greater volume of other oils as naphthas, otherwise unsuited for automobile engines, is at once made usable.

Thei gbject of the invention described herein is to so adjust the conditions controlling the reactions in the vapor-crackingprocess above referred to as to insure the formation of substantial percentages of wild gasolene and to mingle the latter with a heavy oil as naphtha, thereby rendering both constituents usable as motor fuel. It will be understood that simultaneous with the formation of the wild gasolene, large percentages of more readily condensable gasolenes and naphthas are also formed.

In the. accompanying drawings forming a part of this specification, Figure '1 is a View, partly in elevation and partly in section, adapted to the practice of the invention; Fig. 2 and Fig. 3 are similar views illustrating modifications of the apparatus.

In the practice of the invention, hydrocarbons are introduced into the retort 1, under conditions of temperature to insure substantially instantaneous vaporization of the liquid, and the subsequent cracking of the vapors.

For the purposes of this invention it is preferred to maintain a temperature in the furnace 2, employed for the heating of the retort, which ma be of any suitable construction, varying a ove 500 C., and a pressure in the retort ranging above 30 pounds per square inch.

The products of reaction are discharged passed from the receptacles 3 through a condenser 4 (shown in Fig. 3), where lighter products as gasolene are condensed, and the fixed gases and high volatile vapors directed into the scrubbers. In order to save and utilize the wild gasolene which passes from the receptacle 3 or condenser 4 mingled with the fixed gases, this mixture is brought into intimate contact with the naphtha, such as is formed simultaneously with wild gasolene. A desirable means for this purpose consists of a series of tanks 5, partially filled with naphtha and so connected to the recep tacle or condenser and to each' other that the gases and vapors will flow through these tanks in succession. Suitable means are employed to insure the thorough dissemination of the gases and vapors through the naphtha. F or example, masses of broken material6 may be supported by grids 7, suitably arranged in the tanks. As the gases and wild gasolene pass through the tanks, the latter will be gradually taken up by the oil, and a s'uificient number of tanks should be employed to insure the absorption of practically all of the wild gasolene. \Vhen the naphtha in the first tank has absorbed a suflicient amount of wild gasolene to render it usable as a motor fuel, it is drawn off and replaced by the contents of the second tank, which in turn is charged from the third and so on through the series, the last tank being chargedwith fresh naphtha.

In the practice of the vapor phase cracking process above referredto, some of the products have too high a boiling point to permit of their use as a motor fuel, and it has been the practice to subject such higher boiling oils to a second cracking operation. A considerable percentage of such higher boiling oils can be rendered usable as a motor fuel without re-cracking by mingling with it the wild gasolene. By a proper adjustment of reaction conditions, wild gasolene may be produced in sufficient quantities to render usable approximately all the naphtha simultaneously produced.

It Will be understood that any suitable means or method of bringing the wild gasolene into such relation as to permit of the absorption of the wild gasolene, may beemployed. As for example, the tank may be filled with broken material 8, the naphtha fed into the top of the tank and the gases and vapors admitted at the bottom. Or any suitable form of counter current absorber may be used. If desired, the connections from the retort to and through the scrubbers and from the supply of heavy oil, can be supplied with suitably arranged valves, as shown, and-by a proper adjustment of these valves the entire system may be maintained under pressure.

The conditions under which reaction occurs in the vapor-cracking process above referred to may be so adjusted that the amount of wild gasolene produced will be considerably in excess of that required for rendering the naphtha, simultaneously cracked. usable as a motor fuel- In such case, this excess wild gasolene may be employed for treating .naphthas from any other source.

\Ve claim herein as our invention:

The process herein described which consists in subjecting hydrocarbon in a vaporous phase to suitable temperature and pressure conditions for the production in predominant quantities of hydrocarbons boiling below 30 C., condensing the naphtha from the mixed vapors and passing the uncondensed vapors through the naphtha to cause absorption of low-boiling hydrocarbons therein.

In testimony whereof we have hereunto set our hands.

WALTER F. RITTMAN. CLARENCE B. DUTTON. 

